I recently installed Ubuntu on my MacBook pro 5.5 (mid 2009). I have a problem with the brightness control. The thing is, when I try to reduce the brightness of my display which would help my battery life dramaticlly is doesnt work.

I tried to use the system preference but no succes. I tried to look of it changes something if disconnect the computer from the charge I the screen will dimm but once against I failed.

I tried many things such as pommed or Many other little things that I have had read on forums.